U.S. Pat. No. 4,810,658 discloses photometric instruments, their use in methods of optical analysis, and ancillary devices therefor. The method comprises optically analysing a test sample which comprises a sample material with light-absorbing, scattering, fluorescent, phosphorescent or luminescent properties. The sample is partly in a liquid phase and partly bound to an adjacent solid surface. The method comprises providing as said solid surface a surface of a transparent solid optical waveguide, and measuring light from the sample material bound to said solid surface that has passed into and through said transparent solid optical waveguide with total internal reflections and emerged from said waveguide at an angle that deviates from the optical axis of said waveguide.
U.S. Pat. No. 7,750,316 B2 discloses a polymer biochip for detecting fluorescence. The provided optical chip has one or more parabolic optical elements that capture and collimate the fluorescent light and direct it onto a detector. The optical chip may be constructed of a polymer and made using injection molding techniques.
US 2010/0243914 A1 discloses a scanning system that provides for detection based on supercritical angle fluorescence (SAF). The system provides for the optical coupling of a sample to the scanner in a sandwich structure that uses first and second refractive index matching materials to provide optical coupling through the sandwich arrangement.
WO 2011/141530 A2 discloses a sensor comprising a substrate having a first surface and a second surface. The first surface has at least one sensor site provided thereon. The substrate is configured such that on excitation of a sample provided at the sensor site, luminescence originating from the sensor site propagates into the substrate, the second surface of the substrate being configured to selectively transmit the luminescence propagating within the substrates at angles greater than the critical angle out of the substrate where it may be detected by a detector provided below the substrate. A specific type of luminescence mentioned in the WO publication is fluorescence, and more specifically supercritical angle fluorescence (SAF).